Hello guys, I designed a circuit for measuring current and voltage, so I am using a screw terminal(J4) to give my 250V,20amps ac source and another screw terminal(J5) to connect a ac load to it, now traces should be drawn between these two screw terminals, but as its a 2 layer, 2oz/ft, the trace width is 9.6mm, which is very big and as I try to draw it from my first pin of screw terminal(J4), second pin isn’t allowing it, since, its very near, what should I do ?, any suggestions please ?
Use both sides, or increase your copper weight.
hello, I didnt understand use both sides, please can u elaborate, I am a beginner
Reduce your trace width, and draw traces on both sides of the board. You need to check the option to NOT remove redundant traces in the router preferences.
First, don’t post full screen shots, they’re unreadable even when zoomed. The pertinent area is enough.
Second: 20 A through a screw terminal? Don’t go there.
I am already using 2oz/ft thickness, I cant move to 3oz, as my professor suggested me to use 2oz, any otherways to reduce the thickness ?
wont upload screenshots again sorry, and I am using the screw terminals equipped for 50amps, so it can handle 20amps
Like I said - you have two sides on the PCB - use them.
as my second layer is ground plane, can I draw on it ?, sorry for childish questions, I am designing for first time in Kicad
I didn’t say “don’t use screenshots”, I just said only use a relevant cutout, not the whole screen.
Yes, you can draw a trace on it, and it will automatically create a clearance area in the ground plane.
You could also draw traces from opposite sides of the pad, on the top layer.
Alright, but could u help me with what to do, shall I use two 1*1 screw terminals ao that trace will get enough space for 9mm, or any other method to reduce the trace width on a two layer board
should i use via ?, but how will the width reduce if I use via ?
I would surround your connector pins with a “zone” on each side of the connector like this:
Note that my pads aren’t connected, because I didn’t feel like making a schematic.
oh, so if i create a zone around my pin like that, then I can use 9.6mm traces without connecting it with the pins right
That is correct. Just connect the pads to the zone without the use of “thermal” connections (use solid connections).
I am sorry again, please could you tell in a simpler way, as I am still a beginner
First: The combination of 250V, 20A and beginner is not a good combination, so it’s good to read there is a professor looking over your shoulders.
For such high voltages you also need bigger clearances, and combined with the high current, the screw terminal you choose is simply not fit for the task. Choose a bigger screw terminal. KiCad has several footprints for screw terminals with 10mm and a 10.2mm pitch (Stupid banana units) and it also has high current terminals such as for example:
Wuerth_REDCUBE-THR_WP-THRBU_74650073_THR
When you use separate terminals, you can place them as far apart as you like. But the most important thing is to start to select a terminal that is suited for the job.
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There are different options for how pads connect to filled zones - play around with them and you will see what I mean.